The suit, brought in Denver District Court by the right-leaning Mountain States Legal Foundation, alleges the Colorado Bridge Enterprise — an agency created in 2009 — violates provisions of the Taxpayer’s Bill of Rights, or TABOR, in the state constitution. The foundation filed the suit on behalf of the TABOR Foundation.

The suit argues the bridge-building agency has unconstitutionally raised taxes on Coloradans without a vote of the people by imposing a bridge-safety surcharge on vehicles, which the lawsuit argues is a tax and not a fee allowed under TABOR.

“In clear violation of TABOR, the General Assembly enacted and CDOT implemented a scheme to levy taxes and raise revenues without a vote of the people of Colorado,” William Perry Pendley of the Mountain States Legal Foundation said in a statement.

The suit also argues that the agency is not a true “enterprise” of state government, which would allow it to impose fees.

A Democratic-controlled legislature in 2009 passed the Funding Advancement for Surface Transportation and Economic Recovery Act.

Studies cited by lawmakers in support of FASTER pegged the cost needed to maintain Colorado’s roads and bridges at $1.5 billion, a figure far higher than FASTER raises.

The measure raises registration fees by about $40 a year for a typical vehicle, generating an estimated $200 million a year for road and bridge repairs. Roughly half of that fee, an average of $20, supports the Bridge Enterprise.

The state has issued $300 million in bonds to repair 40 bridges, with plans to issue another $400 million to repair a total of 125 crumbling bridges by 2017.

The owners of Boulder’s Sterling University Peaks apartments, who this summer were cited for illegally subdividing 92 bedrooms in the complex, have reached an agreement to settle the case for $410,000, the city announced Thursday.